In recent years, video display devices of rapidly growing popularity, such as plasma displays and liquid crystal displays, are increasingly required to have a plurality of signal receiving interfaces, as more and more video signal supplying devices, such as DVD players, set top boxes being digital broadcast receivers or personal computers, are connected thereto, so that a plurality of such video signal supplying devices can be connected to a video display device.
Patent Document 1 discloses a conventional configuration of a video interface device of a single video display device for receiving video signals from a plurality of video signal supplying devices as described above. An important part of the video interface disclosed in Patent Document 1 will be described with reference to FIG. 5. A video interface device A includes three input signal processing sections C-1, C-2 and C-3 for receiving three channels of video signals B-1, B-2 and B-3 from three video supplying devices (not shown), and a video selection circuit E for selecting a video signal of one channel from among video signals D-1, D-2 and D-3 obtained by performing an input process by the three input signal processing sections C-1 to C-3. The video selection circuit E receives a video switch signal CH-SEL based on a remote controller operation by the operator, for example, from outside, and selects the video signal of one intended channel according to the switch signal CH-SEL.
Patent Document 1: Japanese Laid-Open Patent Publication No. 2004-40208